OBJECTIVE Our objective was to determine if magnesium reduces free radicals generated by direct current countershock and preserves left ventricular contractile function. BACKGROUND We have previously shown that magnesium reduces free radicals in a coronary occlusion-reperfusion model, and therefore also might reduce free radical generation by direct current shocks. METHODS In eight swine we...

John Taylor has produced a comprehensive and insightful paper. He begins by reviewing what he calls the “Great Inflation,” the period of the 1970s and early 1980s. Following Brad De Long’s observation that by the early 1970s, well before the oil shocks, baseline U.S. inflation was already in the 4 percent to 5 percent range, John Taylor rejects the hypothesis that the oil price shocks of the pe...

H useyin Tek, Perry A. Stoll, and Benjamin B. Kimia LEMS, Division of Engineering, Brown University Providence RI 02912 Abstract The extraction of gure symmetry from image contours faces a number of fundamental di culties: object symmetries are distorted due to (i) gaps in the bounding contour of a shape due to gure-ground blending, weak contrast edges, highlights, noise, etc.; (ii) an introdu...

Several cases of exposure to hand-transmitted shocks in two different factories were studied with an intention to improve our knowledge about the influence of the impulsive components of vibration on human being. Two types of shocks affecting the workers could be distinguished, i.e., shocks having small amount of energy at frequencies higher than 100 Hz and shocks having relatively high frequen...

The purpose of this paper is to identify the changes in the impact of energy shocks on economic activity at different phases of economic development – with an interest in assessing if the economy’s vulnerability and resilience to shocks improved. Using data on the United Kingdom over the last three hundred years, the paper replicates a method introduced by Kilian (2008) to disentangle supply, d...

We address the question of whether numerical particle-in-cell (PIC) simulations and laboratory laser-plasma experiments can (or will be able to, in the near future) model realistic gamma-ray burst (GRB) shocks. For this, we compare the radiative cooling time, tcool, of relativistic electrons in the shock magnetic fields to the microscopic dynamical time of collisionless relativistic shocks — th...

Morphological and spectroscopic evidence suggest that shocks may affect the spatial and velocity distributions of gas in the narrow line region (NLR) and extended NLR of some active galaxies. It thus seemed plausible that shocks may also energize the NLR. The observed emission line ratios strongly favor photoionization as the heating source for this gas, but it is not clear whether the ionizing...

The currently available automatic implantable cardioverter-defibrillator has proven highly successful for termination of ventricular tachycardia and fibrillation. Newer devices, however, permit lower energy shocks to be delivered initially and longer episodes of arrhythmia to occur before shocks are delivered. These changes may result in longer durations of arrhythmia before successful terminat...

The currently available automatic implantable cardioverter-defibrillator has proven highly successful for termination of ventricular tachycardia and fibrillation. Newer devices, however, permit lower energy shocks to be delivered initially and longer episodes of arrhythmia to occur before shocks are delivered. These changes may result in longer durations of arrhythmia before successful terminat...